Co-Executive Producer Michael J. Weithorn often sneaks his name onto the set. In one episode, Arthur attempts to sell the "Arthur's head screwdriver" to Weithorn Hardware and in another, Doug's dentist office is in the Weithorn Medical Center.
Arthur (Jerry Stiller) is seen wearing a wedding ring throughout the entire run of the series even though his character is not married. That's because he's a widower on the show. In real-life, he was married to Anne Meara (who played Olchin's mom on the show) for fifty-two years until her death in 2015.
'The King of Queens' is the only television show to feature appearances by all four members of the Stiller family: Jerry Stiller, his wife Anne Meara, his daughter Amy, and his son Ben. The movie "Zoolander" (2001) also featured appearances by all four members of the Stiller family.
In the show's opening, when Doug and Carrie are shown being playful in the grass in front of the Unisphere fountain in Flushing Meadows Corona Park, Arthur can be seen strolling past in the background.
There are pictures on the fridge of Don Geronimo and Mike O'Meara from the nationally syndicated radio show "The Don and Mike Show". The Reference to them not knowing who they were was an inside joke. They also guest appeared in season two, episode ten, "Roamin' Holiday".